Combination rock drill and reamer.



APPLICATION FILED MAY 7, 1912.

Patented Aug. 6, 1912.

IN l/EN TOR WITNESSES:

bmwd A TTORNEY KONRAD JONASSEN, OF TENINO, WASHINGTON.

COMBINATION ROCK DRILL AND REAMER.

Specification of Letters Patent.

Patented Aug. 6,1912.

Application filed May 7, 1912. Serial No. 695,759.

To all whom it may concern:

Be it known that I, KONPAD JoNAssEN, a subject of the King of Norway, and resident of Tenino, in the county of Thurston and State of Washington, have invented certain new and useful Improvements in Combination Rock Drills and Reamers, of which the following is a specification.

My invention relates to means for sinking holes or pockets into rocks, such pockets to serve as receptacles ,for charges of explosives introduced for the purpose of splitting or otherwise dismembering the said rocks.

In order to obtain blocks or slabs of particular shape from a solid rock formation it is necessary to provide means tending to cause the rock to part along certain predetermined lines. This is usually accomplished by sinking a row of holes into the rock along the desired parting line, and by reaming the said holes to a peculiar shape adapted for the purpose specified.

The object of my invention is to provide a simple and eificient device for producing the aforesaid results. More specifically my aim is to combine such drilling and reaming apparatus in one tool, thereby not only saving time of operation but materially simplifying the operation, as will here nafter be fully explained.

In the accompanying drawing, forming part of the specification, Figures 1 and 2 illustrate in front and side elevation a rock drill embodying my invention. Fig. 3 is an end elevation of the drill. Figs. 4 and 5 are cross sectional views taken through the center of Figs. 1 and 2 respectively. Fig. 6 shows a cross section on line CC of Fig. 2. And Fig. 7 illustrates the method of operating upon a rock formation.

My device comprises a shank 1 of any suitable shape and length and made at one end with an enlarged portion or head 2. A central perforation 3 extends the entire length of the device, and'through this perforation air is admitted forthe purpose of blowing the accumulating rock dust away fromthe cutting face of the apparatus.

The drill proper is composed of a series of radially disposed teeth 4. The shape of said teeth may be varied to suit operating conditions, but I have found the shape illustrated in the drawing to give entire satisfact-ion. It is noticed that the cutting edges,

5, of the said teeth are of the same height,

thus presenting a perfectly. level cutting surface.

The head 2 flares out on opposite sides and terminates in two segmental cutters 6, 7, the cutting edges, 8, of which are positioned somewhat behind the drill surface 5. Said segmental cutters form the reamers of my device, and are provided for the purpose of producing a smooth wall in the pockets. Intermediate said reaming cutters are a pair of comparatively narrow projections 9, made with a high inner edge 10, a low outer edge 11, and adjacent, slanting edges 12. These projections, or side cutters, serve to cut narrow grooves in the Wall of the pockets for the purpose of directing the parting of the rock operated upon, as indicated in Fig. 7.

In this "iew 13 represents a rock formation,

into which a series of pockets 14 have been sunk. The grooves, 15, of said pockets all point in direction of line 18, when therefore charges, placed in said pockets, are exploded, the rock will part substantially on said line.

The operation of my device is clear to any one versed in the art, and one advantage of the apparatus is that the drilling and reaming operations are combined, whereby considerable time is saved. Another advantage is that the apparatus is fed into the rock without resorting to the usual turning movement, which is not only difiicult but very tiresome and fatiguing. Finally the head of my device, due to the liberal curve, 19, cuts entirely free, so that it does not stick and can be removed from the sockets without any material effort on the part of the operator.

I claim:

1. In a device of the character described,

in combination, a body comprising a shank and an integral head, said body having a central perforation, the face of said head having radially disposed drill teeth concentric with said perforation. a pair of concentric, segmental reaming lips positioned on opposite sides of said head, and a pair of side cutters intermediate said reaming lips, all for the purpose set forth.

2. A rock drill comprising a hollow body portion flaring at one end to provide clearance in cutting, said flared portion terminating in a pair of segmental reaming cutters, a face drill centrally positioned on said head, and a pair of narrow side cutters intermediate said segmental reamers, all for the purpose set forth. 3. In a rock drill, a body perforated through the center and terminating at one end in a flaring head, drill teeth radially disposed on the face of said head and concentric with said perforation, concentric and se mental reaming cutters encompassing said drill teeth. and having their cuttin face on a lower plane than the face of sai teeth, and a pair of narrow side cutters intermediate said reaming cutters, said side cutters having a wide flare so as to cut deep grooves in the wall of the hole'to be sunk.

4. In a rock drill, a centrally perforated body having at one end a flaring head, ste ped cutters on the face of said head sai cutters comprising an inner circle oi radially disposed drill teeth, segmental reaming cutters arranged on an outer circle, and a pair of narrow, slanting side cutters positioned in the spaces between said se mental cutters, all substantially as set forth.

In testimony whereof, I have hereunto affixed my signature in the presence of two witnesses.

KONRAD J ONASSEN.

Witnesses:

J. SPONSENY, DAVID E. LOFGREN. 

